1. Field of the Invention
The present invention relates to a vehicular voltage regulating system arranged to regulate a voltage (directly input from a battery and not through an ignition switch) to a voltage at a predetermined level and to supply the regulated voltage to an on-board electronic control device which is required to operate even when an ignition switch is turned OFF.
2. Description of the Prior Art
automotive vehicles are recently equipped
Most automotive vehicles recently have been recently equipped with a seat belt system for restraining vehicle passenger seated on a seat. The seat belt system is required to operate so as to restrain the passenger or release the passenger from restraint, even when an ignition switch is turned OFF to stop an engine. Operation of the seat belt system is usually controlled by an on-board electronic control device which is supplied with voltage regulated by a voltage regulating device. The voltage regulating device is arranged to regulate the voltage (directly input from a battery and not through the ignition switch) into a voltage at a predetermined level even when the ignition switch is turned OFF to operate the seat belt system.
Thus, the conventional voltage regulating device is always supplied with the regulated voltage regardless of the ON and OFF states of the ignition switch thereby to maintain the stand-by condition, and therefore a small amount of so-called stand-by current unavoidably flows out from the voltage regulating device to the electronic control device. Such continuous flowing-out of the stand-by current provides possibility of causing overdischarging of the battery.